Injection pain, cardiovascular changes and recovery following induction of anaesthesia with propofol in combination with alfentanil or lignocaine in children.

The effect of pretreatment with alfentanil 10 (Alf10), 15 (Alf15) or 20 (Alf20) micrograms.kg-1 on reducing injection pain caused by propofol was compared with lignocaine 10 mg mixed with propofol (Lign). This double-blind, double-dummy and randomized study included 100 children with a mean age of 4.3 +/- 0.6 years, 25 children in each group, undergoing minor otolaryngological surgery. The children were premedicated orally with midazolam 0.5 mg.kg-1 and atropine 0.03 mg.kg-1. Injection pain occurred in 4% in the Lign group. The corresponding figures were 40, 16 and 20% in the Alf10, Alf15 and Alf20 groups, respectively. Both 1% lignocaine 10 mg and alfentanil 15 micrograms.kg-1 reduced injection pain significantly compared with alfentanil 10 micrograms.kg-1. Pretreatment with alfentanil significantly diminished haemodynamic responses to tracheal intubation. Furthermore, the concomitant use of alfentanil and propofol caused transient severe bradycardia and a significant decrease in heart rate after laryngoscopy.